CD8+ T-cells play a crucial role in eradicating viral infections. The focus of this project is two-fold. First, to study mechanisms that viruses use to subvert CD8+ T-cell responses and second, to understand how primary CD8 + T-cells are stimulated. Despite the importance of T-cells, we do not yet fully understand the induction of a CD8+ T-cell responses and the generation of CD8+ T-cell memory to virus infection. For viruses in which traditional vaccine approaches have not been successful, it is hoped that induction of CD8+ T-cell memory will enhance immunity. To induce optimal CD8+ T-cell responses to vaccines it is necessary to understand how primary CD8+ T-cells are stimulated. This project aims to address the following questions; 1. Following a virus infection in what location are primary TCD8+ cells stimulated? 2. What types of cells are capable of effectively presenting antigen to primary CD8+ T-cells? 3. Is the antigen presenting cell infected, or does it present viral proteins obtained from infected cells? 4. How do the answers to questions 1-3 vary between different antigens encoded by the same virus and the same antigen encoded by different viruses?